This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. Primary support for the subproject and the subproject's principal investigator may have been provided by other sources, including other NIH sources. The Total Cost listed for the subproject likely represents the estimated amount of Center infrastructure utilized by the subproject, not direct funding provided by the NCRR grant to the subproject or subproject staff. Hepatitis C virus (HCV) infection is a major cause of chronic liver disease and hepatocellular carcinoma. NS4B protein plays a key role in creating the environment for HCV replication and induced alterations in cells that result in the formation of a tight structure consisting of vesicles called membranous web. We have performed pullout experiments to identify interacting partners of NS4B proteins.